Spain's world-famous opera star Montserrat Caballe has died in Barcelona, a source at the hospital where she was being treated has said.
Caballe died early Saturday at Hospital San Pau in Barcelona, hospital spokesman Abraham del Moral told The Associated Press.
The singer, who was known as one of the world's greatest voices during a career spanning half a century, had long suffered from ill health and was hospitalised in mid-September due to a gall bladder problem, local media reported.
Caballe starred in 90 opera roles with almost 4,000 performances.
"The Spanish soprano sang with us on a number of occasions between 1972 and 1992 and inspired millions over the course of her career with her stunning voice", it said in a statement on Twitter.
She released the song "Barcelona" with the Queen frontman in 1987 - and it was used again during the 1992 Barcelona Olympics, a year after Mercury's death.
She had stints with the Basel Opera and Bremen Opera before her worldwide breakthrough in 1965 in Lucrezia Borgia at Carnegie Hall in NY.
"Her personality and her unique voice will always be with us".
The performance won her great acclaim from the public and made her an overnight sensation.
Caballe performed the song live, accompanied by a recording of the late Mercury, at the 1999 UEFA Champions League soccer final in Barcelona's Camp Nou stadium. "Your attractive voice will be with us forever".
She was ordered to pay €254,000 and accepted a six-month suspended jail sentence as part of a deal with prosectors.
In 1964, she married tenor Bernabe Marti and one of their children, Montserrat Marti, is also a soprano.